The Jaguar XJR-14 is a

sports-prototype A sports prototype, sometimes referred to as simply a prototype, is a type of race car that is used in the highest-level categories of sports car racing. These purpose-built racing cars, unlike street-legal and production-based racing cars, are n ...

racing car introduced for the 1991

World Sportscar Championship The World Sportscar Championship was the world series run for sports car racing by the FIA from 1953 to 1992. The championship evolved from a small collection of the most important sportscar, endurance, and road racing events in Europe and No ...

season. It was designed by

Ross Brawn Ross James Brawn (born 23 November 1954) is a British Formula One managing director, motor sports and technical director. He is a former motorsport engineer and Formula One team principal, and has worked for a number of Formula One teams. Serv ...

and John Piper, and was built and run by

Tom Walkinshaw Racing Tom Walkinshaw Racing (TWR) was a motor racing team and engineering firm founded in 1976, in Kidlington, near Oxford, England, by touring car racer Tom Walkinshaw. The company initially handled privateer work before entering works touring car r ...

(TWR), on behalf of

Jaguar Cars Jaguar (, ) is the luxury vehicle brand of Jaguar Land Rover, a British multinational car manufacturer with its headquarters in Whitley, Coventry, England. Jaguar Cars was the company that was responsible for the production of Jaguar cars ...

Design

The 1991 season marked the introduction of the

FIA FIA is the Fédération Internationale de l'Automobile (English: International Automobile Federation), the world's governing body for all forms of motor sport where four or more wheels are used. Fia or FIA may also refer to: People * Fia Backst ...

’s new, and controversial, 3.5 Litre Formula which replaced the highly successful

Group C Group C was a category of sports car racing introduced by the FIA in 1982 and continuing until 1993, with ''Group A'' for touring cars and ''Group B'' for GTs. It was designed to replace both Group 5 special production cars (closed top touri ...

category that had been used in the World Sports Car Championship since 1982. However, due to a small number of entries in the new 3.5 litre formula heavily penalised Group C cars were allowed participate in the newly created C2 category for the 1991 season but Jaguar participated in the new formula. To comply with the new regulations Jaguar produced an all-new car, the XJR-14. It was designed by

and John Piper, and was built by

(TWR). In the past, TWR's Jaguars had been designed under the direction of

Tony Southgate Tony Southgate (born 25 May 1940, Coventry, England) is a British engineer and former racing car designer. He designed many successful cars, including Jaguar's Le Mans-winning XJR-9, and cars for almost every type of circuit racing. He was res ...

, while Brawn worked with a large design staff (12 according to John Piper); a paradigm shift (albeit small) in its own right and reflective of Brawn's Formula One background. The abandonment of the Group C fuel consumption regulations meant a change in aerodynamic design philosophy. Coupled that with vastly different packaging requirements for a small, light, normally aspirated engine meant that concerns over drag became a secondary requirement to downforce. The new design, lower kerb weight of and higher downforce levels meant that the XJR-14 was a lot faster in corners compared to the previous Group C front runners.

Engine

The primary feature of the new regulations centred on 3.5-litre

naturally aspirated engine Naturally may refer to: ;Albums * ''Naturally!'', an album by Nat Adderley * ''Naturally'' (Houston Person album) * ''Naturally'' (J. J. Cale album) * ''Naturally'' (John Pizzarelli album) * ''Naturally'' (Sharon Jones album) * ''Naturally'' ...

s. Although the XJR-14's predecessor, the XJR-11, used a twin turbo-charged 3.5-litre engine derived from the

Metro 6R4 The Metro is a supermini car, later a city car that was produced by British Leyland (BL) and, later, the Rover Group from 1980 to 1998. It was launched in 1980 as the Austin mini Metro. It was intended to complement and eventually replace the M ...

-derived JV6 engine, in order to comply with the new rules the two turbochargers would have needed to be removed. Naturally this wasn't a realistic option, nor was it ever considered, given the design compromises of not using a bespoke engine. But given the Jaguar-Ford connection, it was decided to utilise the 3.5-litre Ford HB V8 Formula One power plant. Developed by Geoff Goddard and most notably used by the Benetton Formula One team, but now badged as a Jaguar, the Ford HB was detuned to about 11,500 rpm (compared to about 13,000 rpm) and aimed to produce slightly less power (about vs. around 700 bhp) with aims at enhanced reliability.

Race results

Three chassis were built and used for 1991: 591, 691, & 791. In the early part of the 1991 World Sportscar Championship season the XJR-14 was in a league of its own, totally outclassing its rivals and in particular the

Peugeot 905 The Peugeot 905 is a sports-prototype racing car built by Peugeot's racing department, Peugeot Talbot Sport. The car was initially unveiled in February 1990 and was developed throughout 1990 before making its race debut in the final two races of ...

and

Mercedes-Benz C291 The Mercedes-Benz C291 was a sports-prototype racing car introduced for the 1991 World Sportscar Championship season. It was Mercedes-Benz’ final car in the Group C category. Introduction The 1991 season marked the introduction of the FIA’s ne ...

. Only the opening race went Peugeot's way, but that was seen more as a result of luck than the 905's competitiveness. The fact that Jaguar already had a race proven engine certainly helped the team’s cause, but the rest of the car was far superior to its rivals. It wasn't until midway through the season that the Jaguar met its match through Peugeot's new 905B. This meant a hard fight with the new and quickly improving Peugeot squad for the rest of the season, but Jaguar was able to hold on and secure the manufacturers title with 3 victories. At the 1991 24 Hours of Le Mans, Jaguar initially entered two XJR-14s but later decided that the XJR-14 would not be capable of finishing the distance due to unknowns in the development of the Cosworth HB to last 24 hours. Jaguar instead decided to enter three older XJR-12s which entered in the C2 class. Although the XJR-12s did not manage to win, Jaguar's decision not to run the untested XJR-14 was vindicated by the fact that Peugeot's 905 failed to finish the race. Mercedes also withdrew its C291 in favour of its older

C11 C11, C.XI, C-11 or C.11 may refer to: Transport * C-11 Fleetster, a 1920s American light transport aircraft for use of the United States Assistant Secretary of War * Fokker C.XI, a 1935 Dutch reconnaissance seaplane * LET C-11, a license-build var ...

models. After 1991, Jaguar decided not to continue in Group C, believing that they had spent enough time in Group C and the instability of rules recently in the World Sportscar Championship. Opting against further development of the XJR-16, TWR sent the XJR-14 to the United States for the 1992 IMSA Camel GTP championship. Chassis 691 (Rebadged as #192) debuted at the 1992 Grand Prix of Miami where it broke the track record by four seconds. Without a major upgrade to the suspension and with the car unable to deal with the high G loads of U.S circuits, the XJR-14 was unable to beat the latest challengers from Toyota and Nissan, forced to finish third in the championship with only two victories. Jaguar continued to use the three updated 1991 chassis throughout the season.

Derivatives

Meanwhile, TWR had reached an agreement to supply more XJR-14 chassis to

Mazda , commonly referred to as simply Mazda, is a Japanese multinational automotive manufacturer headquartered in Fuchū, Hiroshima, Japan. In 2015, Mazda produced 1.5 million vehicles for global sales, the majority of which (nearly one m ...

, minus the Cosworth V8s but installed with Mazda-badged Judd V10s for the

. Mazda would rebadge the XJR-14s as MXR-01s. The MXR-01 was essentially a productionised XJR-14 and as there had been no ongoing development they ended up not being particularly competitive, scoring no wins and finishing third in the championship. Several years later, TWR would resurrect XJR-14 chassis #691/192 for the development of a new prototype for Porsche. They renamed the car the TWR-

Porsche WSC-95 The Porsche WSC-95 (sometimes referred to as the TWR WSC-95) was a Le Mans Prototype originally built by Tom Walkinshaw Racing. It was modified by Porsche from the original Group C Jaguar XJR-14 from which it derived, and run by Joest Racing. Ori ...

. Its most significant feature was that it had the roof removed, turning it into an open cockpit prototype to run under the then-new LMP regulations. The WSC-95 would carry a Porsche 3.0L turbocharged Flat-6. After chassis #691 was modified, TWR built a second WSC-95 from scratch. In both the

1996 File:1996 Events Collage.png, From left, clockwise: A Centennial Olympic Park bombing, bomb explodes at Centennial Olympic Park in Atlanta, set off by a radical Anti-abortion violence, anti-abortionist; The center fuel tank explodes on TWA Flight 8 ...

and 1997 24 Hours of Le Mans, the TWR-Porsches were able to take the overall win. See Chassis Log.

Chassis log

591 - 1991: Suzuka (DNF), Monza (1st), Silverstone (3rd), Autopolis (2nd). 1992 : Laguna Seca (4th), Road America (crash in warm-up). Rebuilt to running order at TWR, sold to US collector (2003-2009). Sold to Chamberlain-Synergy, England (2009-2015) Location : MecAuto, Belgium, since 2015. 691/192 - 1991: Suzuka (DNF), Monza (2nd), Silverstone (1st), Nurburgring (2nd), Magny Cours (3rd), Mexico (did not race), Autopolis (3rd), Sugo (1st). 1992 (chassis number changed to 192): Mid-Ohio (1st), New Orleans (4th), Watkins Glen (3rd), Laguna Seca (3rd), Portland (DNF), Phoenix (2nd), Del Mar (3rd-DNF). Converted to a Porsche WSC95 Spyder in late 1994, raced at Le Mans in 1996 and 1997 by Reinhold Joest, winning the race on both occasions. Location : now in Reinhold Joest's private museum. 791 - 1991: Nürburgring (1st), Magny Cours (5th), Mexico (6th), Sugo (9th). 1992: Miami (6th-DNF), Road Atlanta (1st), Lime Rock (accident in race). Rebuilt by Retract Composite and Lanzante Motorsport. Now as Show Car. Location : Previously England with same owner as X91 in 2014-2015, but since sold and exported to the U.S. in 2017. X91 : New chassis tub built in 2003 before TWR liquidation. Location : Lanzante Motorsports, South of England (2003-2014). Sold in 2015 to new owner in England.

References

External links

Jaguar XJR-14 Technical Analysis
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Jaguar XJR-14 website
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Jaguar XJR-14 on WikiF1
{{Jaguar modern timeline XJR-14 Group C cars IMSA GTP cars